title: Factors that might impact intrathecal drug delivery (IDD) dose escalation: a longitudinal study.
abstract: BACKGROUND
  Intrathecal drug delivery (IDD) system with implantable pumps has been used to treat cancer-related pain as well as noncancer-related chronic pain. Opioids, including morphine and hydromorphone, are the most commonly used intrathecal (IT) agents. Although technology, techniques, and knowledge of IDD have improved, dose escalation occurs relatively rapidly in noncancer pain.
  
  
  METHODS
  Retrospective chart review of IDD pump patients, implanted for a minimum of 2 years, was designed to investigate possible existing predictors that might impact IDD dose escalation, such as patient's demographic risk factors, duration of the treatment, and diagnosis of the patient's pain correlates with increase in medication requirement. Primary outcome was defined as the annual percent escalation in daily opioid dosage, and secondary outcome was the average annual percent reduction in VRS pain scores.
  
  
  RESULTS
  Median dosage escalation was 17% per year for patients with neuropathic pain compared with 12% per year for patients with other pain modalities. Mean opioid dosage increased 30.4% more rapidly for patients with neuropathic pain than for other pain modalities. The adjusted difference in means was 28.8% (P = 0.001). None of the secondary exposures were statistically significant after the Bonferroni adjustment. No association was found between pain modality and annual percent change in VRS pain score.
  
  
  CONCLUSIONS
  Annual increases in daily opioid dosage were higher among patients with neuropathic pain than among patients with other modalities; we also found no evidence of difference in annual pain reduction.
authors.affiliation: Evidence-Based Pain Management Research, Cleveland Clinic, Cleveland, Ohio, U.S.A.; Department of Pain Management, Cleveland Clinic, Cleveland, Ohio, U.S.A.
authors.forename: Nagy
authors.initials: N
authors.lastname: Mekhail
authors.forename: Ramatia
authors.initials: R
authors.lastname: Mahboobi
authors.forename: Armin
authors.initials: A
authors.lastname: Farajzadeh Deroee
authors.forename: Shrif
authors.initials: S
authors.lastname: Costandi
authors.forename: Jarrod
authors.initials: J
authors.lastname: Dalton
authors.forename: Maged
authors.initials: M
authors.lastname: Guirguis
authors.forename: Pankaj
authors.initials: P
authors.lastname: Mehta
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage*; D016503:Drug Delivery Systems; D057286:Electronic Health Records / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D007278:Injections, Spinal / Q000379:methods*; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement; D012189:Retrospective Studies
chemical_list: D000701:Analgesics, Opioid
keywords: dose escalation predictors; implantable; infusion pumps; intraspinal drug delivery; intrathecal opioids; neuropathic pain